Poole is helping Travel + Leisure resolve once and for all a question that's been around since the dawn of commercial flight: what is the correct way to put your luggage in the overhead bin on an airplane?

“Wheels first,” said Poole. “Most passengers know their large carry-on items go in the overhead bin wheels first. Jackets and coats go on top of the bag. Smaller bags go under the seat.” Write that down.

Wheels first makes it easier for passengers to grab the bag when leaving, making getting off the plane faster, which is something everyone wants.

As planes modernize and adapt to the realities of travel needs, bins get bigger, which in turn changes the rules for properly stowing your luggage.

“If you're lucky enough to find yourself on a plane with the newer, taller bins, you can put them in wheels first, but on their side,” said Poole. That simple design upgrade translates into more space so that more bags can fit into the overhead bin. What this really means: more travelers can skip baggage claim and just get on with their trip.

Naturally, there are a few times that the wheels-first rule can be broken, though.

“There are still a few older planes flying around with the bins that are too short for wheels first, so you'll have to put them in long ways,” Poole said, but notes that there’s a serious downside to sideways bag storage. “That takes up so much room and doesn't leave much space for every passenger to bring on a bag—a flight attendant's nightmare.”

Another thing that sets flight attendants off? Lifting heavy bags into overhead bins. “I might help [lift the bag], but I won't do it for them,” said Poole. “If I went around lifting everyone's heavy bag I'd be out of a job. Chiropractors are expensive.”

Poole has other overhead bin-related pet peeves and it’s unlikely that she’s the only flight attendant (or traveler, for that matter) to find this behavior aggravating.

“Some passengers, I think, believe they own the entire overhead bin directly above their seat,” said Poole. “I constantly have to remind people that we share the bins.”

She also wants to make one point of overhead bin etiquette absolutely clear: If the bin above your seat is full, it's okay to use one a few rows back. What’s not okay, though, is to take another passenger's bag out of an overhead bin to make room for your own.

“I've seen that happen twice,” said Poole. “Both times I made the passenger put the first bag back and find another bin.”